Bulldozer



Deg. 5, 1939. i

J. S. STEWART BULLDOZER Filed April 28, 1937 5 Sheets-Sheet 3 Dec.5,1939. J STEWART 2,182,412

BULLDO ZER Filed April 28, 1937 s Sheets-Sheet 4 4 D ec. 5, 1939.

.1. s STEWART.

BULLDOZER Filed April 28, 1937 5 Sheets-Sheet 5 Patented Dec. 5, 1939PATENT OFFICE BULLDOZEB James Samuel Stewart, Long Beach, Calif., as-

signor to Wayne D. Crook Application April 28, 1937, Serial No. 139,500

tclalms.

My invention relates to a bulldozer and is of a type usually used withan endless track type of tractor. Such type of tractors are generallyrequired for heavy work to have sumcient weight and to give thenecessary traction for bulldozing large and heavy masses of material. Itis to be understood however, that my invention applies to wheeled typeof tractors. With but slight modification my invention may be used withthis latter type and designed for less heavy work.

One of the objects and features of my invention is the construction ofthe various parts of the bulldozer so that with but slight change thesecan be used with many difierent typesof tractors; particularly. of theendless track type. A characteristic of this type of tractor is that ithas what might be termed a chassis frame on which is directly supportedthe engine, that is the power plant, the operators seat and the variouscon- 2 trols. A winch or cable drum is usually mounted at the rear endof this chassis frame back of the drivers seat and manipulated by aclutch. The winch is used for winding in and letting out the cable forlifting and lowering the, bowl of the bulldozer and is also used forother work for which the tractor may be adapted. These tractors have anendless track frame which is usually connected to the chassis frame atthe rear end without any spring connection or with very heavy rigidsprings whereas the forward end of the endless track frame is connectedto the chassis frame by a spring mount ng. thus allowing either endlesstrack at the forward end to climb over obstructions which may not be metby theopposite track. This action of one track climbing up on anobstruction or for instance the opposite side dropping into adepressiomsives a lift or drop invention provides for a' verticaladjustment of the trunnions' at the rear end of the arms. Thus 50 thesetrunnions may be given a relatively high or low position in referencetothe endless track frame to which they are connected adjacent the rearportion of such frame. 0

Another characteristic and feature of m in- 55 vention is in themounting of the two side beams which extend longitudinally of thetractor above the upper run of the tread, these extending forwardly ofthe power plant and the chassis. Such beams aresupported on two columnsor posts. The main post is connected to the endless track frame adjacentthe forward drive wheel of the endless track. This post takes the loadand the tension at the rear end of the beam is carried by a rear postalso connected to the endless track frame adjacent the rear drivingwheel and in 10 proximity to the trunnion connection of the thrust armsto such endless track frame. The side beams are thus of a cantilevertype passing along and above the upper run of the endless track havingthe forward end as above mentioned extending in front of the chassisframe. A further characteristic of the position of support of the twoside cantilever beams is that the vertical center of the thrust load,that is, of the forward thrust posts, is substantially over the centerlongitudinal line of the endless tracks. To obtain this constructionthese cantilever beams considered in plan converge from their reartension support posts towards their forward ends located in front of thechassis frame and in front of the power plant. These beams thereforepass across the endless track on each side in a somewhat diagonalmanner. s

A further characteristic of my invention is so mounting asubstantialcross beam'on the forward ends of the cantilever supportingbeams. As this beam carries the sheaves over which operate the cableconnected to the bowl, this beam is mounted in bearings to swivel on ahorizontal 35 transverse axis to accommodate the cables to the angle oflead to the bowl. Also to accommodate the diil'erence of elevation ofone cantilever beam to its mate on the opposite side when for instancethe forward end of one of the tracks is either elevated or depressed inrelation to the other track, I provide the cross shaft bearing in a ballor spherical bearing or bushing. This also is constructed to permit aslight change in length between the two bearings. This accommodates atilt considered relative to the horizontal of the cross beam whereas thebowl may be horizontal when the rear end of a tractor is substantiallyhorizontal. 7

One of the disadvantages of many of the pres- 5 cut types of bulldozersmounted on endless track type of tractors is that the cable leads fromthe n winch located at the rear end of the tractor is carried through atube along one side of the tractor in a high position from the rear endto the forward end of one of the cantilever beams from which end thecables lead to the cross beam. As it sometimes happens that bulldozersof this type upset sidewise on their work, the operators have beenfrequently trapped or caught by this high cable lead in not being ableto jump clear of the machine.

Therefore anotherfeature of my invention is mounting the cantilever sidebeams in a relatively low position as to the endless track and chassisframe and having a sharply upturned neck at the forward end of eachbeam, thejournals for the cross beam with the cable sheaves at the topof the upturned neck. One of these cantilever beams functions as ahousing for the cable leads extending along one side of the machine fromthe winch to a guide sheave, which leads the cable to the sheaves on thecross beam.

My invention is illustrated in connection wit the accompanying drawings,in which:

Fig. 1 shows a side elevation of my invention together with a sideelevation of an endless track type of tractor to which it is connected.

Fig. 2 is a plan partly broken away taken in the direction of the arrow2 of Fig. 1 of the thrust arm and bowl construction illustrating theadjustable vertical attachment of the trunnion end.

Fig. 3 is a rear elevation of the bowl removed from the thrust arm andmay be considered as taken in the direction of the arrow 3 of Fig. 1 or4.

Fig. 4 is a vertical section of the bowl taken on the section line 6-6of Fig. 3-in the direction'of the arrows. I

Fig. 5 is an underneath view of the bowl taken in the direction of thearrow 5 of Fig. 3 or 4.

Fig. 6 is a plan of one of the cantilever beams taken in the directionof the arrow 50f Fig. 7.

Fig. '7 is an elevation of the beam of Fig. 6 taken in the direction ofthe arrow 7 of such figure.

Fig. 8 is a vertical transverse section on the line 8-8 of Fig. 7 in thedirection of the arrows.

Fig. 9 is a bottom view taken in the direction of the arrow 9 of Fig. 7.

Fig. 10 is a front elevation of the swivel cross beam from which thebowl is suspended and may be considered as taken in the direction ofthe.

arrow ill of Fig. 1 or 11.

Fig. 11 is a plan of the beam of Fig. 10 partly broken away taken in thedirection of the arrow ii of Fig. 10. Y '1 Fig. 12 is an elevationviewed from the inside of the upturned neck on the end of one of thecantilever beams used as a lead for the operating cable for the bowl,such elevation beingtaken Fig. 1, my invention employs opposite sidethrust arms designated by the assembly numeral i I. .These arepreferably formed hollow and substantially rectangular in crosssectionwith a substantially uniform taper from the rear portion I! tothe front end portion IS. The rear end hasattached thereto an abutmentpiece i4, (note Fig. 2) this being shown as having an internal neck ISwith a shozl'der about the neck against which the small end It abuts andis sec red by welding or the like. The abutment piece has adjustingvertical teeth It and back of such teeth there is a vertical shoulderslot I! through preferably a solid portion 8. The trunnion assembly is acasting having upper and lower plates 2! and a vertical connecting web22 from which web there extends laterally a hub section 23 (note Fig.2). This hub section has an inner flange 2a. The upper and lower platesare spaced apart the proper distance so that the assembly may be securedto theframe of the endless track of the tractor by means of boltspassing through'bolt holes 25. It will be noted that the web has smallvertical ribs 25 engaging certain of thesebolts. A terminal socket has afront end 3i with teeth 32 to interlock with the teeth it on the end ofthe solid portion it of the abutment piece it. A cap 33 fits on thefront 39 and this whole assembly is secured by a pair of bolts 3extending throughbolt holes in the cap and the forward piece, thesebeing threaded into a .nut or the like in the shouldered vertical slotii; A bolt 35 extends through the hub 23 with its head fitting in asocket on the inside and passes through a clamping plate 36. there beinga nut on the out= side. The terminal socket is thus mounted for a slightrotation on the hub 23 between the flange 2t and the plate 36. Thevertical adjustment to the trunnion end of the arm ii is done byloosening the bolts 3d and then i e-adjusting the engagement of theteeth it and 32 respectively and again clamping these bolts. It willthusbe seen that the rear end of the thrust arms may be ad- J'ustedvertically and that they also trunnion or have a slight swivel with thecenter of the hub 23 as the axis is swivelled.

The large or forward end it of the thrust arms has a contact end 410 toengage a complementary portionof the bowl hereinunder described and atthetop and bottom is provided with complementary ears Iii and 412 (noteFigs. 1 and 2). There is also a pair of spaced ears 63 on the top andspaced ears M secured to the inside surface d5 of each thrust arm, byinside surfaces is meant the portion which is contiguous to the tractor.

Referring to the construction of the bowl desig-.

nated by the assembly numeral 5t (note particularly Figs. 1 through 5),this has a bowl plate 5i curved with a convex curve on the front sidewith a reverse bend '52 at the topand a horizontal top plate portion 53.The lower portion of the bowl plate 5% is substantially tangent to thecurve of the upper part. At each side of the' bowl there is a verticalside plate 55. This plate has a front edge 56 extending fromsubstantially the reverse bend 52 at the top to the lower edge 51 of thetangential section 56 of the bowl plate. This side plate extends aconsiderable distance back of the bowl, being illustrated as having arear edge 58 connected by a curve 59 to the upper edge 60 of such plate.These two opposite side plates are parallel and thus parallel to asecond line through the tractor. A pair of rectangular thrust tubes areconstructed from the back of the bowl plate extending rearwardly, thesehaving vertical side walls 66 and t1 and topand bottom walls 6t and 69(note Fig. 3) terminating and.'l2, these. being inclined inwardlytowards the axial center and they align with the ears 6| on the forwardend of 'the thrust arms ll so that attaching pins 13 may be driventhrough the eyes in these complementary ears,-the pins preferably havinga cotter pin manner of connection or bolts may be used. In this mannerthe bowl at its lower portion is firmly and rigidly secured to the endsof the twosthrust arms.

The back of the bolt is reinforced by a lower somewhat horizontal plate15 and an upper similar horizontal plate 16. These extend the fulldistance between the end plates 55 (note particularly Figs. 3, 4 and 5)and are secured by welding or the like to the'top and bottom'walls 69 ofthe short rectangular tube 65. A series of vertical webs 11 connectthese plates. There is also a pair of diagonal brace plates 18 extendingfrom one comer 19 of the square short tube 65 to their converging upperends 80 underneath the horizontal section 53 of the bowl plate 5I. Atthe intersections 8| with the horizontal upper reinforcing plate 16there is a welded connection.

From the ears 43 there is a brace bar 82. extending upwardly to a pairof cars 83 on the back of the mold board of the bowl adjacent the top ofthe bowl. There is also a substantially horizontal brace bar 84extending from the ears 44 on the thrust arm to a pair of cars 85 on theback of the mold board. These brace bars are connected to the respectiveears by pins or bolts or the like. It will be seen by this constructionthat the bowl which has formed integraltherewith the various braceplates may be disconnected from the forward end of the thrust arms I Ibut when connected as above described, the thrust arms and the bowl forma rigid structure in which there can be no slip or pivoting movement.

The cantilever beam construction designated by the numeral I00 is shownparticularly in Figs.-

1, 6, 7, 8 and 9. These two beams are hollow in cross section and areformed from an inside and an outside channel ml and I02 connected bycentral welds I 03 extending lengthwise on the upper and lower surfaces(note Fig. 8). These cantilever beams have a thicker vertical sectionI04 at the center, a reduced vertical end section I05 adjacent thetension support and also a reduced vertical section I06 at thecantilever end portion. The beams are of substantially constant widthconsidered horizontally. The center thrust support or post designated II0 has a longitudinal web III which by means of a right angular bend II2terminates in a horizontal section II3, this being welded to theunderside of the thick center section I04 of the ca'ntileverbeam. Aheavy outside ribI I4 extends from the vertical section H3 and is weldedto the outside face of the beam. The web at its top and forward edge hasa somewhat triangular flared gusset plate I I5 which is welded to theforward edge II6 of the web and at II1 to the underside of thecantilever beam. This gusset plate extends considerably forward of the.web and thus gives additional strength to the cantilever end section ofthe beam.

The lower or foot portion designated I I8 of the thrust support or postis constructed to conform to the particular tractor frame on which thesupport and the cantilever beam is mounted. An angle H9 is secured tothe inside of the web III. angle may be considered as having a verticalflange I20 and ahorizontal flange I2I. The upper edge of the flange I20is sloping as.

indicated at I22. At the rear end of the .horizontal flange an angleboss I23 is secured by welding or the like, this having a gusset braceI24. The projecting portion has a bolt hole l25. A rectangular plate I26is welded to the horizontal flange I2I projecting inwardly. beyond theinner edge and this has a bolt hole I21. A heavy vertical web I28 iswelded on the inside of the web II I and to the vertical flange I20 ofthe angle H8 and also to the horizontal flange I2I. has a U shapedcut-out section I28 with a downwardly projecting spaced end I30 to whichis welded a horizontal shoe I3I having a bolt hole I32. Thecharacteristics of this construction of the thrust support is that thefoot portion II8 may be secured to the tractor frame, that is, the

- portion of the frame carrying the endless tracks so that the upper runof the track operates in the space below the horizontal section I13 andabove advisable to have a lower angle I34 which has a vertical web I35welded both to the web III and to the vertical web I20 of the angle II8.This has a horizontal flange I36. The two angles H8 and I34 may besubstantially the same length and between these is fitted a plate orangle element of the frame of the structure.

The tension support I40 (note Figs. 6 and '1 has an end cast piece Ipreferably tubular in cross section and welded at a socket joint I42 tothe rear portion of the cantilever beam.- This tapers and has a verticalstrap I43 with bolt holes I44 for bolting to the frame of the tractor.It will be obvious that this tension end structure will be modified andchanged to suit the particular tractor to which the assembly of thebulldozer is attached. One or both of the cast pieces I has a tubularsocket end I45 forming an opening into the center of the beam for acable guide as hereinunder detailed. Reinforcing fillets I46 and I41strengthen the connection of the tension support to the rear end of thecantilever beam.

At the forward end of each cantilever beam there are neck pieces I50 andI5I. The neck piece I50 is preferably of suitable casting secured to theforward end of one of the cantilever beams which is rectangular in crosssection by a recessed welded 7 section I52- This casting is preferablymade rectangular in cross section and is bent upwardly with a sharpupward bend indicated at I53 (note Fig. 6) and has a spherical bearingI54 at its upper end (note Fig. 10), the bearing hav-' .purpose of thisconstruction is for mounting a sheave swivel I65 (note Fig. 14). This ispreferably made of-a casting havinga hub section I66 witha rear and aforward circular end I61 and I68. This casting is provided with twooppositeplates I connected by straps I10 between .which isfltted asheave I1 I. This assembly is inserted in the sheave journalingstructure shown in detail in Figs. 12 and 13 in which the rear end- I61fits in the rear bearing section I51. The opposite end I68 flts in thebearing end I58 and is held in the clamp. By removing theclamp thesheave swivel I may be inserted and clamped in place. This occupies theposition shown in Fig.

The swivel crossbeam designated by the assembly I is shown particularlyin Figs. 10 and 11 in which three vertical plates are used designatedI18, I11 and I18. These have upper edges I18. Sliort rectangular platesI8I and I8I' are fitted in the bottom edges I88 and the top edges I19respectively adjacent the ends of the beam. The center plate I11 has acut-out section I82 in which is fitted the inner end of a. cylindricalshaft I83. This is welded to the cut-out section of plate I11 and alsoto the top plate I8I' as indicated at I88. This makes a rigid and strongconstruction in which the shafts I83 may be considered as integral withthe beam assembly I15. Slldably mounted on each shaft I88 is a ball I85,such ball being spherical on its outside surface is mounted in thebearing I54 and is held in place by the cap I55.

The cable connection from a winch usually positioned at the rear end ofthe tractor is defined by the cable assembly I98 (note particularlyFigs. 1, 3, 4, 10,11 and 14). Connected to the rear end of one of thecantilever beams, such being illustrated as on the right hand side ofthe tractor facing forwardly there is a guide tube IIII which is fittedin the tubular socket I45 secured to the rear end of the cantileverbeamadjacent the tension support. This is secured by welding or the like.tubemay be welded or otherwise fastened to the frame of the tractor andhas an open rear end to receive the rear portion I93 of the cable I94.

The rear end part leads to a winch mounted at the back of the tractor,such winch being not illustrated as it forms no part of my immediateinvention. The cable leads upwardly on a slope through the inside of thecantilever beam I88:

which is shown as being hollow and rectangular in cross section. Aforward lead' I95 enters the sheave swivel I85 through the rear endportion I81 and makes a right angle turn at the sheaves I 1| Atransverse lead I98 (note Fig. 10) leads to one of the idler sheaves ofwhich there are two, I91 and I98 located between the center plate I11and the outer plates I18 and I18 of the beam assembly. These sheaves aremounted on a short shaft I89 extending through the plates.

From these sheaves on the swivel beam there are two drop leads 288 tothe sheave assembly 285 (note Figs. 3 and 4) mounted on the back of thebowl. This assembly includes a sheave block 288 whichhas ears 281connected to a lug 288 connected to the back-of the bowl preferablymounted on the horizontal plate 18. A bolt 288 attaches the sheaveblock. The sheave 2") is mounted in this block. A bolt 2| I permits theready disassembling of the sheave. The cable has a dead end section 2I2secured to a dead and care of any slight change of the distance apart ofthe neck ends of the cantilever beams due to for instance the forwardend of one endless track of the tractor engaging a hump or being in a,.depression in the ground. The swivel action of the sheave swivel I85takes, care of any slight 1 changes of angularity between the swivelbeam The rear portion I92 of the I18 and the cantilever beams I88. Bythis arrangement it will be seen that although the bowl maintains aconstant position relative to the rear end of the tractor, that theforward ends of the cantilever beams will vary 'their position inrelation to the forward end of the tractor due to the, up and downmotion of one side or the other of the front part of the endless trackbut no matter how these positions vary, there is always a cor-- rectlead for the cable operating the bowl without any binding action. Itwill also be noted by this construction that the cable is led forwardlyfrom the winch in a low position so that there is no obstructionadjacent the drivers compartment or cab of the tractor.

Various changes may be made in the details of the construction withoutdeparting from the spirit or scope of the invention as defined'by theappended claims.

I claim:

1. In a bulldozer, the combination of a pair of thrust arms having abulldozer bowl connected between the forward ends of said arms, the rearend of each arm being provided with an abutment piece, a trunnionassembly having a hub, means to attach the hub to the frame of atractor, the hub having a terminal socket mounted for rotation on theaxis of the hub and means to adjust the abutment piece vertically as tothe terminal socket to thereby change the position of the thrust arms inreference to the axis of rotation of said arms and hence to the frame ofthe trac-' tor, the means to adjust the abutment piece comprisinginterengaging teeth between the abutment piece and the terminal socketand bolts clamping the abutmentpiece to the terminal socket, the saidteeth being arranged substantially vertical.

2. Ina bulldozer the combination or a pair or cantilever beams, eachbeam having a thrust supporting post, said post having a portion thereofoffset 'to one side of the place of connection to" each of the saidbeams having a straight vertical beam having a tension supporting postadjacent its rear end with means on said post to connect to the endlesstrack frame of the tractor in a position whereby each beam which has asubstantially straight central plane intersects the endless vtrackdiagonally, the beams converging towards their forward ends.

4. In a bulldozer, the combination of a pair ,of cantilever beams, eachhaving a substantially straight vertical. longitudinal plane, the saidplanes converging at the front with the rear portion of each beam thusbeing spaced apart wider than the center portion, the center portion ofeach beam being supported on a thrust supporting post, each post havingan upper horizontal portion connected to the underside of each beam andhaving a vertical web portion offset out-- wardly from the verticalplane through the beam, each thrust post having a lower or foot portionwhereby the vertical center line of the beam at its point of connectionto the post is substantially in the longitudinal central vertical planeof the upper and lower endless tracks of the tractor, each beam having atension supporting post adjacent its rear end, each tension post havingmeans for attachment to the endless track frame of the tractor, at leastone of the beams being hollow and having a hollow guide structureconnected thereto at the rear end of the beam for passage of anoperating cable from the rear por- I tion of the tractor forwardlythrough said hollow 5. In a bulldozer, the combination of a pair ofcantilever beams having means for support from the frame of a tractor,each beam having a sharply upturned neck adjacent its forward end, aswivel cross beam journaled at the upper portion of the upturned necks,one of the beams being hollow and having a lead of an operatin cableextending therethrough, a sheave swivelly connected to the forward endof the hollow beam, the cable leading thereover, the swivel cross beamhaving sheaves to which the cable connects from the hollow cantileverbeam, the sheaves of the swivel beam being adapted to lead the cable toa sheave operatively connected to a bulldozer bowl.

6. In a bulldozer as claimed in claim 5, each of the cantilever beamshaving substantially a straight upper surface leading from the rearportion of each upturned neck, the swivel sheave of bearing, a ballmounted in each bearing, a cylindrical shaft extending through each balland a swivel cross beam fixedy connected to each shaft whereby the crossbeam may swivel on the axis of the said shafts, also the beam with thesaid shafts 5 v may slide slightly through the balls and each shaft maytilt with the ball thereon in regard-to the spherical bearing, theswivel cross beam having sheaves, one of the cantilever beams beinghollow and having an operating cable extending 10 therethrough, a swivelsheave connected to the hollow cantilever beam below the sphericalbearing, the cable leading through the hollow beam over the swivelsheave to the sheaves of the swivel cross beam, the said cable beingadapted to lead to sheaves operatively connected to a bulldozer bowl.

8. In a bulldozer, the combination of a pair of longitudinally extendingcantilever beams having a tension support at the rear end of each beamand a thrust support positioned forwardly thereof, the tension and thethrust supports having means for attachment to the frame of a tracton oneach side thereof, one of the beams having an opening therethrough forpassage of a cable 35 and a cable extending through said opening fromaposition rearwardly of the tension support to a position adjacent theforward end 'of the beam having the opening, such beam having a sheaveat the forward end, the cable passing thereover, '0 a pair of thrustarms pivotally mounted on the frame of the tractor and having a bowl anda connection from the part of the cable forward of the sheave to thesaid bowl for raising and lowering the bowl relative to the forward endsofsaid I beams, the bowl being concave on the forward side and convex onthe rear side considered in a vertical plane and having means forattaching the arms on the opposite sides of the bowl adjacent the.bottom thereof, a diagonal brace rib ex- 0 tending upwardly fromadjacent the lower side corner of the bowl on the rear side, the.saidbrace ribs converging at the center of the bowl adjacent the upperedge and a sheave mounted on the back of the bowl substantially belowthe center 5 line of convergence of the said ribs.

JAhlES s'rswan'r.

